If Democrats take control of the U.S. Senate, that could lead to laws that shake up key sectors such as tech, health care, finance and energy — especially if the Nov. 3 election brings a “blue wave” that puts Joe Biden in the White House.
So which Senate races are worth tracking, as 35 seats in that 100-member chamber are up for grabs in 2020?
The nonpartisan Cook Political Report has rated 10 seats as solidly Republican and 10 as solidly Democratic as of Thursday, meaning the independent newsletter’s analysts view 15 races as competitive, with ratings that range from “Toss up” to “Lean D” or “Likely R.”
Key Senate races in 2020
|State||Incumbent candidate||Other candidate(s)||FiveThirtyEight forecast||Cook rating|
|1. Arizona||Martha McSally (R)||Mark Kelly (D)||79% chance for D win||Lean D|
|2. Colorado||Cory Gardner (R)||John Hickenlooper (D)||79% chance for D win||Lean D|
|3. Maine||Susan Collins (R)||Sara Gideon (D)||63% chance for D win||Toss up|
|4. Alabama||Doug Jones (D)||Tommy Tuberville (R)||75% chance for R win||Lean R|
|5. North Carolina||Thom Tillis (R)||Cal Cunningham (D)||67% chance for D win||Toss up|
|6. Iowa||Joni Ernst (R)||Theresa Greenfield (D)||53% chance for D win||Toss up|
|7. Montana||Steve Daines (R)||Steve Bullock (D)||68% chance for R win||Toss up|
|8. Georgia (1)||David Perdue (R)||Jon Ossoff (D)||72% chance for R win||Toss up|
|9. Georgia (2)||Kelly Loeffler (R)||Doug Collins (R), Raphael Warnock (D)||51% chance for R win||Toss up|
|10. South Carolina||Lindsey Graham (R)||Jaime Harrison (D)||76% chance for R win||Toss up|
|11. Kansas||N/A, incumbent retiring (R)||Roger Marshall (R), Barbara Bollier (D)||74% chance for R win||Lean R|
|12. Alaska||Dan Sullivan (R)||Al Gross (D)||77% chance for R win||Lean R|
|13. Michigan||Gary Peters (D)||John James (R)||79% chance for D win||Lean D|
|14. Texas||John Cornyn (R)||MJ Hegar (D)||87% chance for R win||Lean R|
|15. Kentucky||Mitch McConnell (R)||Amy McGrath (D)||96% chance for R win||Likely R|
Sources: Cook Political Report and FiveThirtyEight data as of 10/15/20
Republicans are the incumbents in 13 out of the 15 competitive races. The GOP currently has 53 seats in the Senate, so Democrats need a net gain of four seats to take control of the chamber — or just three if Biden wins the presidential contest, because a Democratic vice president, Kamala Harris, would cast tie-breaking votes.
Henrietta Treyz, director of economy policy at Veda Partners, said in a note last week that Democrats “now have a 55% chance of securing 50 seats in the Senate and upwards of 85% odds of winning the White House.”
Meanwhile, FiveThirtyEight has given a 73% chance for a Democratic takeover of the Senate as of Thursday, and Height Capital Markets analysts also put it at 73% as of Wednesday. Height’s team has warned that it could take time to determine the winner of this year’s Senate contests.
“Even as investors are beginning to discount the possibility of a period after the election in which presidential winner is not known for weeks, the chances of uncertainty about control of the Senate are rising,” the analysts said in a note last week.
Recent gains for U.S. stocks SPX, +0.01% have been pinned in part on investors becoming less concerned about a contested presidential election. Biden has an edge of 4.9 percentage points over President Donald Trump in a RealClearPolitics average of polls focused on top swing states, and betting markets tracked by RCP give the Democratic challenger a 65% chance of beating the Republican incumbent.
Democrats took control of the House of Representatives in the 2018 midterm election and are widely expected to remain in charge there after this November’s voting. The party lost its grip on the Senate in 2014’s midterm election, when Republican candidates picked up seats in key battleground states.
This is an updated version of a report first published on Oct. 9, 2020.